Spatial structure systems built by joining elements of nodes and bars have long been used in the state of the art. Each node element can be joined to various bars in different directions and each bar is joined to two nodes, one at each end, so that, by means of these two types of elements, three-dimensional structures with widely variable configurations can be built.
Examples of these systems can be found in, for example, U.S. Pat. No. 4,905,443, U.S. Pat. No. 5,074,094 or U.S. Pat. No. 6,378,265, in which different systems of this type are described, and which, relying on the aforementioned nodes and bars, enable substantially rigid structures to be built.
However, these documents all have the same problem, which consists in the possibility of correcting the structure once it is built without having to disassemble the whole structure, or at least a large portion thereof.
In order to solve this problem, configurable modular spatial structures have been developed, which not only enable easy assembly but also simple disassembly, where furthermore, because of the design of their components, torsion stress generated in the interconnecting bars between the nodes can be relieved. An example of these systems can be found in document ES 2362845 which belongs to this same applicant.
However, even though the spatial structure of said document perfectly fulfills the requirements for which it was designed, both the disassembly and the number of elements involved are potential areas for improvement.
Specifically, the disassembly comprises two main aspects. One is the improvement of joint resilience in order to further facilitate unit disassembly. This is mainly due to the fact that the portion of washer described in ES 2362845, due to its design, may not be sufficiently resilient at times, which prevents the washer from entirely regaining its initial state when the retaining screw is removed, that is to say, it loses resilience, thus encumbering said disassembly.
Furthermore, due to the forces applied on the assembly once it has been mounted, the washer is trapped inside the groove at the end of the bar, preventing the disassembly of said bar or causing it to be dragged out in the event of disassembly.